[bug-OpenMage#884] Add missing methods to category collection class

These two methods exist on Mage_Catalog_Model_Resource_Category_Flat_Collection
but not on Mage_Catalog_Model_Resource_Category_Collection so if flat categories
is enabled but they are being temporarily rebuilt and any frontend code relies
on these methods, calls to these methods will generate PHP errors since the
flat collection and eav collection classes expose a different set of methods
on the public API.

app/code/core/Mage/Catalog/Model/Resource/Category/Collection.php

@@ -362,6 +362,29 @@ protected function _getCurrentStoreId()
         return (int)Mage::app()->getStore()->getId();
     }
 
+    /**
+     * Add filter by path to collection
+     *
+     * @param string $parent
+     * @return $this
+     */
+    public function addParentPathFilter($parent)
+    {
+        $this->addFieldToFilter('path', array('like' => "{$parent}/%"));
+        return $this;
+    }
+
+    /**
+     * Add store filter
+     *
+     * @return $this
+     */
+    public function addStoreFilter()
+    {
+        $this->setProductStoreId($this->getStoreId());
+        return $this;
+    }
+
     /**
      * Add active category filter
      *